Tuning coil



F. SWINK.

TUNING COIL. APPLICATION men nus. 1920.

Patented Nov. 14, 1922.

ATTORNEY Patented Nov. 14, 1922.

PATENT OFFICE.

FLOYD SWINK, OF ST. LOUIS, MISSOURI.

TUNING COIL.

Application filed May 8. 1920.

To a l] whom it 272 (14 concern.

Be it known that I. FLoYn b'wnvn, a citir zen of the l nited States, residing at St. Louis, in the county of St. Louis and State of Missouri, have invented new and useful Improvements in Tuning Coils, of which the following is a specification.

This invention relates to a tuning coil and has for its primary object the construction of a tuning coil that is more accurate in its operation and which can be more sensitively adjusted.

An object of the invention is the construction of a tuning coil having wider adjustment than the commercial apparatuses now on the market.

With theseand other objects in view the invention will be better understood from the following detailed description taken. in connection with the accompanying drawing wherein:

Fig. l is a side elevation of the tuning coil.

Fig. 2 is a diagrammatic view.

Again referring to the drawing illustrating one manner in which my invention may be constructed the numeral 1 designates a base supporting the upright cylinder 2 upon which is supported the coil sections 3, 4t, 5, 6, 7, and 8. These sections are separated from each other by the rings 9 which also support the cylinder. T'hese rings are electrically connected to the terminals of the coil sections. Each ring is formed with a rod section 10 all of which are connected to but insulated from each other to form the vertical rod 11. Each rod section has mounted thereon a slidable contact 12 having a finger piece 13 and spring contact 14. arranged for sliding movement over the Serial No. 379,917.

convolutions of the coil sections. Support ed by the base 1. is a switch board 15 carrying a plurality of switch points 16 that cooperate with the switch arm 17. Each point 16 is electrically connected to a rod section as clearly shown in Fig. 2.

From this construction it will be seen that by adjusting the arm 17 over the points 16 a number of coil con'volutions arranged in circuit with the electrical devices may be changed and to accomplish a more accurate adjustment the sliding contacts may be individually moved for cutting out one or more convolutions of any section.

It is, of course, to be understood that the invention may be constructed in various other manners and the parts associated in different relations and, therefore, I do not desire to be limited in any manner except as set forth in the claims hereunto appended.

Having thus described my invention What I claim is:

1. A tuning coil comprising a base, a cylinder upstanding therefrom, coil sections wrapped upon the cylinder and electrically connected, rod sections secured to but insulated from each other, a sliding contact for each rod for cutting out one or more con volutions of a coil section, and a multipoint switch having each point electrically con- 7 nected to a rod section.

2. A tuning coil comprising a base, a cylinder upstanding therefrom, coil sections wrapped thereon and electrically connected together, a rod extending parallel to the cylinder and consisting of insulating sections, and a sliding contact on each section cooperating with the convolutions of said coil.

In testimony whereof I afiix my signature.

FLOYD SVVINK. 

